654690991 has 2 divisors, whose sum is σ = 654690992. Its totient is φ = 654690990.

The previous prime is 654690983. The next prime is 654691001. The reversal of 654690991 is 199096456.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 654690991 - 2³ = 654690983 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (654690901) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 327345495 + 327345496.

It is an arithmetic number, because the mean of its divisors is an integer number (327345496).

Almost surely, 2^654690991 is an apocalyptic number.

654690991 is a deficient number, since it is larger than the sum of its proper divisors (1).

654690991 is an equidigital number, since it uses as much as digits as its factorization.

654690991 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 524880, while the sum is 49.

The square root of 654690991 is about 25586.9300815866. The cubic root of 654690991 is about 868.3179686749.

The spelling of 654690991 in words is "six hundred fifty-four million, six hundred ninety thousand, nine hundred ninety-one".